Tabitha Babbitt is credited to be the inventor of the first circular saw for use in a saw mill in the first half of the 1810s. It is speculated whether or not she was the first to invent it as she was a member of a religious group, Shakers, that prohibited applying for patents, so because there is no patent, controversy surrounds this invention. The only proof that this invention existed is in Shaker lore. According to it, Babbitt noticed two men using one whipsaw, but their motion was wasted, because the saw would cut the wood only when it was being pulled forward. Babbitt thought that a round saw would solve the efficiency problem and created a prototype attaching a circular blade to her spinning wheel, using the pedal of her wheel to power it.